In direct marking systems, the media is held down flat while being printed and hence, media flatness is critical. Usually media is held down by vacuum and transported using media vacuum-transport systems. A typical media vacuum-transport system includes a belt which can be rotated around a vacuum plenum. The belt includes a plurality of holes and it is through the plurality of holes that a vacuum is applied and the media is held down by the vacuum. The interface of the media and the plurality of holes is an important parameter as it has a significant influence on other key vacuum force factors—such as blower size, hole pitch, hole diameter, total flow, etc. One of the disadvantages of conventional media vacuum-transport systems is that they normally employ smooth surfaces on belts, drums, etc., which creates a “sealing-off” effect, thus limiting the applied vacuum force to the area of the belt-holes only. As a result of the localized force application, transport systems have to use oversized blowers, large belt-holes, and inefficient patterns.
Hence, there is a need for a new method for enhancing vacuum pressure distribution for improved media hold down performance in a vacuum transport system.